Stock centering chuck



A. E. MEUNIER STOCK CENTERING CHUCK July 13, 1948.

2 Sheets-Sheet 1 Filed June 10, 1945v Inventor fi ler? EMezz/nzier Bj Wand

y 1948- I A. E. MEUNIER 2,445,147

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Patented July 13, 1948 UNITEDQSTATES PATENT OFFICE Albert E. Meunier,South Attlebcro, Mass. Application June 10, 1943, Serial No. 490,357

1 Claim. (CI. 77-18) This invention relates to a novel and improvedcentering chuck for forming lathe-centers in work to be turned inlathes, the same being adapted for centering either cylindrical ortapered shanks.

My primary aim is to provide a specially constructed chuck which isindustrially appropriate, expertly balanced and of great utility, andwhose parts are such as to save both time and money in machine shops byeliminating tedious prickpunching the center, and doing away with thepresent method of laying out the work with special calipering tools.

In reducing to practice the preferred embodiment of the invention, Ihave conceived an arrangement of carefully chosen parts coordinated toprovide a mechanically superior, compact and convenient and simple andreliable structure achieving the desired results with efficiency andcertainty, whereby to permit practical and expedient use of conventionalcountersinking tools.

Other features and advantages will become more readily apparent from thefollowing description and the accompanying illustrative drawings.

In the drawings, wherein like numerals are employed to designate likeparts throughout the views:

Figure 1 is a side elevational view of a chuck constructed in accordancewith the principles of the present invention.

Figure 2 is a central sectional view, with parts in elevation,illustrating the particular construction and arrangement of said parts.

Figure 3 is an end elevational view of the construction, that is, a viewobserving Figure 1 in a direction from left to right.

Figure 4 is a perspective view of one of the especially designedradially extensible and retractible work-engaging jaws.

Figure 5 is an elevational view of the face of the head showing theradial guideways, the remaining parts being removed for clarity ofillustration of the construction.

Figure 6 is a detail horizontal section on the plane of the line 66 ofFigure 3 looking in the direction of the arrows.

Referring now to the detailed description of the explicit constructionrepresenting the preferred embodiment of the invention, the chuckcomprises what may be conveniently described as a relatively stationaryhead I. This comprises a substantially cylindrical portion having anend- The body 9 tapers, as at In, and merges into a reduced cylindricalneck portion II. The portions I0 and II are formed with a socket l2 toaccommodate the spindle portion of the shank or shaft l3. This spindleportion 14 is socketed centrally to accommodate the tool or center drilll5, the latter being retained in place by the set screw IS. Theintermediate portion of the body constituting the juncture between parts9 and I0 is provided with a bearing to accommodate the tool IS. Theusable end of the tool projects through and beyond the apertured socketinto the cavity which serves to accommodate the work (not shown). Thebody 9 is provided with circumferentially spaced, radial grooves H toaccommodate the radially projectible and retractible chuck jaws l8.These are in the form of substantially rectangular blocks of theconfiguration shown in Figure 4 and have the work-engaging faces l9shaped to conform to the general cylindrical contour of the work, Eachjaw is provided with opposed ribs 20, these being confined and slidablein the countergrooves or keyways 2!. Each jaw is also provided with anadjusting stem or pin 22' screw threaded, as at 23, The threaded endsextend outwardly and beyond the circumferentially spaced cam slots 24provided in the oscillatory adjusting ring or cap 25. The part 25 isproperly matched up and provided with an endless flange 26 fitting andturnable in the guideway or channel 8. Incidentally, the numeral 21designates assembling screws. It will be noticed that the periphery ofthe body 9 is milled or knurled, as at 2B. The peripheral grippingsurface of the oscillatory adjusting cap or ring 25 is likewise knurledat 29, whereby to provide convenient finger grips for actuating theparts in relation to each other.

- Suitably knurled cap nuts 30 having tool holes 3| are carried by theprojecting threaded ends 23 of the respective pins 22.

In operation and to adjust the chuck for required sizes, simply loosenthe clamping or binding nuts 30. This permits the ring 25 to be rotatedor oscillated in relation to the body 9. To open the chuck, the ring 25is turned in an anticlockwise direction, while to close it, it is turnedin a clockwise direction. Obviously, the turning of the ring brings thecam slots into play and these exert thrust pressure upon the pins 22',thus moving the three chuck jaws simultaneously radially in or out,depending on the direction of rotation of the ring. In this manner, thework is effectively centered in relation to the drill l5 to provide thedesired countersunk socket.

It is believed that the construction is reliable, accurate and easy touse and handle. It is susceptible of repair and assembly. It saves time,and is, therefore, a production device.

It is thought that persons skilled in the art to which the inventionrelates will be able to obtain a clear understanding of the inventionafter considering the drawings. Therefore, a more lengthy description isregarded as unnecessary.

Minor changes in shape, size and rearrangement of details coming withinthe field of invention claimed may be resorted to in actual practice, ifdesired.

I claim:

A stock centering chuck comprising a circular body having an axial shanksocket in its inner end and a larger axial Work-receiving socket in itsouter end, Said body further having an axial opening connecting saidsockets ,and provided with radial grooves opening at their inner endsinto the work-receiving socket, a shank for said body having its outerend portion fitted in said shank socket and formed in said outer endportion thereof with an axial tool socket, a tool secured insaid socketand projecting through said axial opening into said work-receivingsocket, radially adjustable work-centering jaws slidable in said radialgrooves and having forwardly projecting threaded stems, a manuallyadjustable cap for said jaws secured on the outer end of said body forlimited rotation relative to the latter, said cap having a centralwork-admitting opening and a series of cam slots about said centralopening through which said threaded stems project, and clamping nutsthreaded on said threaded stems outwardly of said adjusting cap forsecuring the latter in rotatably adjusted positions and, the jaws inradially adjusted positions.

AIIBERT E. MEUNIER.

REFERENCES CITED The: following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 271,941 Sleeth et a1 Feb. 6, 1883443,775 Libby Dec, 30, 1890 835,698 Bartholomaus Nov. 13, 1906 921,568Townsend May 11, 1909 970,679 .Brenneisen -Sept. 20, 1910 1;244,953Bu-dlong Oct. 30, 1917 1,309,217 Ratheram July 8, 1919

